From e5567afa5cfa19e45f93c9c8796e46187a2d12f4 Mon Sep 17 00:00:00 2001 From: Bob Moore Date: Thu, 10 Apr 2008 19:06:38 +0400 Subject: ACPICA: Fix for update of the Global Lock Handle Fixed a problem where the global lock handle was not properly updated if a thread that acquired the global lock via executing AML code then attempted to acquire the lock via the AcpiAcquireGlobalLock interface. Signed-off-by: Bob Moore Signed-off-by: Alexey Starikovskiy Signed-off-by: Len Brown --- drivers/acpi/events/evmisc.c | 13 +++++++++++++ drivers/acpi/events/evxface.c | 9 +-------- 2 files changed, 14 insertions(+), 8 deletions(-) (limited to 'drivers/acpi/events') diff --git a/drivers/acpi/events/evmisc.c b/drivers/acpi/events/evmisc.c index 2d34663dc1e..d075062f5b8 100644 --- a/drivers/acpi/events/evmisc.c +++ b/drivers/acpi/events/evmisc.c @@ -460,6 +460,19 @@ acpi_status acpi_ev_acquire_global_lock(u16 timeout) acpi_ev_global_lock_thread_id = acpi_os_get_thread_id(); acpi_ev_global_lock_acquired++; + /* + * Update the global lock handle and check for wraparound. The handle is + * only used for the external global lock interfaces, but it is updated + * here to properly handle the case where a single thread may acquire the + * lock via both the AML and the acpi_acquire_global_lock interfaces. The + * handle is therefore updated on the first acquire from a given thread + * regardless of where the acquisition request originated. + */ + acpi_gbl_global_lock_handle++; + if (acpi_gbl_global_lock_handle == 0) { + acpi_gbl_global_lock_handle = 1; + } + /* * Make sure that a global lock actually exists. If not, just treat * the lock as a standard mutex. diff --git a/drivers/acpi/events/evxface.c b/drivers/acpi/events/evxface.c index e210aa2d76d..412cae69831 100644 --- a/drivers/acpi/events/evxface.c +++ b/drivers/acpi/events/evxface.c @@ -782,15 +782,8 @@ acpi_status acpi_acquire_global_lock(u16 timeout, u32 * handle) acpi_os_get_thread_id()); if (ACPI_SUCCESS(status)) { - /* - * If this was the first acquisition of the Global Lock by this thread, - * create a new handle. Otherwise, return the existing handle. - */ - if (acpi_gbl_global_lock_mutex->mutex.acquisition_depth == 1) { - acpi_gbl_global_lock_handle++; - } - /* Return the global lock handle */ + /* Return the global lock handle (updated in acpi_ev_acquire_global_lock) */ *handle = acpi_gbl_global_lock_handle; } -- cgit v1.2.3